body{
        background-color: orangered;
        font-family: Arial, sans-serif;
        display: flex;
        justify-content: center;
        align-items: center;
        height: 100vh;
        margin: 0;
}
.container{
        text-align: center;
}
h1 {
        color: #fff;
        font-size: 40px;
        margin-bottom: 5px;
        text-shadow: -1px 0 black, 0 1px black, 1px 0 black, 0 -1px black;
}

h2 {
        color: #fff;
        font-size: 30px;
        margin-bottom: 20px;
        text-shadow: -1px 0 black, 0 1px black, 1px 0 black, 0 -1px black;
}
.calculator{
        width: 300px;
        background-color: #f4f4f4;
        padding: 20px;
        border-radius: 10px;
        box-shadow: 0 0 10px black;
        margin-bottom: 20px;
}
#display{
        width: 90%;
        margin-bottom: 20px;
        padding: 10px;
        font-size: 25px;
        text-align: center;
        border-color: black;
        border-radius: 5px;
        background-color: #fff;
}
.keys{
        display: grid;
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
}
button{
        padding: 10px;
        font-size: 18px;
        border-color: black;
        border-radius: 5px;
        background-color: #ddd;
        cursor: pointer;
}
button:hover{
        background-color: #ccc;
}